hostapd(hidl): Add asynchronous failure callback

Changes in the CL:
a) Add a new callback registration mechanism for the hostapd HIDL interface.
b) Use the existing |setup_complete_cb| callback provided by the hostapd
core to trigger the new onFailure() HIDL callback.

Bug: 112705137
Test: Manual test. Simulated the issue reported in the bug and ensured
that UI toggled off.
Change-Id: I7211e313c107be3a4a7a52af69ffe1e565b5147b
7 files changed